The present invention relates to a washing apparatus, in particular an apparatus which can be used to wash parts exposed to the passage of a flow of loose material.
The apparatus disclosed can be used in particular in the chemical and/or pharmaceutical and/or food industry and in all cases involving the use of loose material consisting of powders, granulated materials, pellets, tablets, capsules or the like.
Above all, in the chemical and pharmaceutical industry, said loose materials must be handled in a substantially hermitic way, so that the spread of powders in the surrounding environment is kept within extremely tight limits.
The importance of the above-mentioned problem increases proportionally with the level at which the substances handled consist of chemical compounds or substances that are not easily degradable in the environment and in some cases potentially toxic or harmful.
Moreover, obviously, when passing from the processing of a first material to the processing of a second, different material, all parts exposed to the passage of the first loose material must be thoroughly cleaned.
The following description refers, by way of example and without in any way limiting the scope of the inventive concept, to a part exposed to said loose material which consists of a valve device of the type that can be used in an apparatus for unloading loose material from a dispensing unit to a user unit.
Said valve device normally consists of a first butterfly valve integral with the dispensing unit, a spacer element and a second butterfly valve integral with the latter.
Each butterfly valve has a flat disk-shaped shutter element that rotates in both directions about a horizontal axis between a position in which the lower end of the dispensing unit is closed, with the shutter lying in a substantially horizontal plane, and an open position, with the shutter lying in a substantially vertical plane, allowing the material to be unloaded from the dispensing unit to the user unit or machine which uses the loose material for subsequent processing.
At the end of loose material unloading, the dispensing unit valve and the spacer valve are closed and, before the dispensing unit is separated from the other parts, the inside of the valve device is washed.
Said washing is normally carried out using directional nozzles giving onto the internal surface of the spacer element, to clean the surfaces of the two valves which will be in contact with the external environment.
However, the solution just described is not without disadvantages, mainly due to the considerable dimensions of the valve device which make its thorough washing difficult.
Moreover, the use of nozzles arranged on the side surface of the spacer element does not guarantee thorough cleaning of the valves and in particular of their central zone.